Wireless Control Module (WCM)

U0019-CAN B BUS

For a complete wiring diagram, refer to the Wiring Information. Electrical Diagrams

- When Monitored:
Continuously

- Set Condition:
Whenever the CAN B Bus (+) or CAN B Bus (-) circuit is open, shorted to voltage or shorted to ground.





1. CHECK FOR ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)s
1. With the scan tool, read the active DTCs.
2. Cycle the ignition switch from off to on at least 5 times, leaving the ignition on for a minimum of 90 seconds per cycle.
3. With the scan tool, read the active DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 2

No

- If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.

2. CHECK TIPM DTCs
1. With the scan tool, read TIPM active DTCs.

Does the scan tool display any CAN B BUS DTCs - ACTIVE?

Yes

- Go to and perform the appropriate diagnostic procedure.

No

- Go To 3

3. (D55) CAN B BUS (+) CIRCUIT OPEN
1. Turn the ignition off.
2. Disconnect the negative battery cable.
3. Disconnect the WCM connector.
4. Disconnect the TIPM connector.
5. Measure the resistance of the (D55) CAN B Bus (+) circuit between the TIPM harness connector and the WCM harness connector.

Is the resistance below 2.0 ohms?

Yes

- Go To 4

No

- Repair the (D55) CAN B Bus (+) circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test

4. (D54) CAN B BUS (-) CIRCUIT OPEN
1. Measure the resistance of the (D54) CAN B Bus (-) circuit between the TIPM harness connector and the SKREEM harness connector.

Is the resistance below 2.0 ohms?

Yes

- Replace the Wireless Control Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test

No

- Repair the (D54) CAN B Bus (-) circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test